1 files changed, 134 insertions, 0 deletions
diff --git a/src/test/fuzz/util.h b/src/test/fuzz/util.h
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+++ b/src/test/fuzz/util.h
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+// Copyright (c) 2009-2019 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_TEST_FUZZ_UTIL_H
+#define BITCOIN_TEST_FUZZ_UTIL_H
+
+#include <amount.h>
+#include <arith_uint256.h>
+#include <attributes.h>
+#include <optional.h>
+#include <script/script.h>
+#include <serialize.h>
+#include <streams.h>
+#include <test/fuzz/FuzzedDataProvider.h>
+#include <test/fuzz/fuzz.h>
+#include <uint256.h>
+#include <version.h>
+
+#include <cstdint>
+#include <string>
+#include <vector>
+
+NODISCARD inline std::vector<uint8_t> ConsumeRandomLengthByteVector(FuzzedDataProvider& fuzzed_data_provider, const size_t max_length = 4096) noexcept
+{
+    const std::string s = fuzzed_data_provider.ConsumeRandomLengthString(max_length);
+    return {s.begin(), s.end()};
+}
+
+NODISCARD inline std::vector<std::string> ConsumeRandomLengthStringVector(FuzzedDataProvider& fuzzed_data_provider, const size_t max_vector_size = 16, const size_t max_string_length = 16) noexcept
+{
+    const size_t n_elements = fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, max_vector_size);
+    std::vector<std::string> r;
+    for (size_t i = 0; i < n_elements; ++i) {
+        r.push_back(fuzzed_data_provider.ConsumeRandomLengthString(max_string_length));
+    }
+    return r;
+}
+
+template <typename T>
+NODISCARD inline std::vector<T> ConsumeRandomLengthIntegralVector(FuzzedDataProvider& fuzzed_data_provider, const size_t max_vector_size = 16) noexcept
+{
+    const size_t n_elements = fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, max_vector_size);
+    std::vector<T> r;
+    for (size_t i = 0; i < n_elements; ++i) {
+        r.push_back(fuzzed_data_provider.ConsumeIntegral<T>());
+    }
+    return r;
+}
+
+template <typename T>
+NODISCARD inline Optional<T> ConsumeDeserializable(FuzzedDataProvider& fuzzed_data_provider, const size_t max_length = 4096) noexcept
+{
+    const std::vector<uint8_t> buffer = ConsumeRandomLengthByteVector(fuzzed_data_provider, max_length);
+    CDataStream ds{buffer, SER_NETWORK, INIT_PROTO_VERSION};
+    T obj;
+    try {
+        ds >> obj;
+    } catch (const std::ios_base::failure&) {
+        return nullopt;
+    }
+    return obj;
+}
+
+NODISCARD inline opcodetype ConsumeOpcodeType(FuzzedDataProvider& fuzzed_data_provider) noexcept
+{
+    return static_cast<opcodetype>(fuzzed_data_provider.ConsumeIntegralInRange<uint32_t>(0, MAX_OPCODE));
+}
+
+NODISCARD inline CAmount ConsumeMoney(FuzzedDataProvider& fuzzed_data_provider) noexcept
+{
+    return fuzzed_data_provider.ConsumeIntegralInRange<CAmount>(0, MAX_MONEY);
+}
+
+NODISCARD inline CScript ConsumeScript(FuzzedDataProvider& fuzzed_data_provider) noexcept
+{
+    const std::vector<uint8_t> b = ConsumeRandomLengthByteVector(fuzzed_data_provider);
+    return {b.begin(), b.end()};
+}
+
+NODISCARD inline CScriptNum ConsumeScriptNum(FuzzedDataProvider& fuzzed_data_provider) noexcept
+{
+    return CScriptNum{fuzzed_data_provider.ConsumeIntegral<int64_t>()};
+}
+
+NODISCARD inline uint256 ConsumeUInt256(FuzzedDataProvider& fuzzed_data_provider) noexcept
+{
+    const std::vector<unsigned char> v256 = fuzzed_data_provider.ConsumeBytes<unsigned char>(sizeof(uint256));
+    if (v256.size() != sizeof(uint256)) {
+        return {};
+    }
+    return uint256{v256};
+}
+
+NODISCARD inline arith_uint256 ConsumeArithUInt256(FuzzedDataProvider& fuzzed_data_provider) noexcept
+{
+    return UintToArith256(ConsumeUInt256(fuzzed_data_provider));
+}
+
+template <typename T>
+NODISCARD bool MultiplicationOverflow(const T i, const T j) noexcept
+{
+    static_assert(std::is_integral<T>::value, "Integral required.");
+    if (std::numeric_limits<T>::is_signed) {
+        if (i > 0) {
+            if (j > 0) {
+                return i > (std::numeric_limits<T>::max() / j);
+            } else {
+                return j < (std::numeric_limits<T>::min() / i);
+            }
+        } else {
+            if (j > 0) {
+                return i < (std::numeric_limits<T>::min() / j);
+            } else {
+                return i != 0 && (j < (std::numeric_limits<T>::max() / i));
+            }
+        }
+    } else {
+        return j != 0 && i > std::numeric_limits<T>::max() / j;
+    }
+}
+
+template <class T>
+NODISCARD bool AdditionOverflow(const T i, const T j) noexcept
+{
+    static_assert(std::is_integral<T>::value, "Integral required.");
+    if (std::numeric_limits<T>::is_signed) {
+        return (i > 0 && j > std::numeric_limits<T>::max() - i) ||
+               (i < 0 && j < std::numeric_limits<T>::min() - i);
+    }
+    return std::numeric_limits<T>::max() - i < j;
+}
+
+#endif // BITCOIN_TEST_FUZZ_UTIL_H